106 DISEASES OF THE BESPIBATOBY ORGANS. 



far as the first rib, and anteriorly and posteriorly to the sixth ri 

 the large posterior lobe extends back as far as the eleventh or twell 

 vertebra, where it extends upward and lies between the vertebra a: 

 the diaphragm. The left lung has a small incision near the he£ 

 called the heart incision. The right lung is somewhat larger th; 

 the left, and extends as far back as the twelfth or thirteenth v( 

 tebra; it is divided into four lobes; the posterior lobe is conside 

 ably larger than the corresponding lobe of the left lung. T 

 cardial lobe lies upon the heart, almost surrounding that orgai 

 the other lobes hold the same relation as they do in the left lun 

 The middle lobe of the lungs is a club-shaped portion that lies 

 a special groove in the mediastinum, extending anteriorly as far 

 the heart and posteriorly to the diaphragm. 



In making an examination of the lungs we must take into co: 

 sideration the shape of the cavity of the chest, sensitiveness 

 pressure, the number and character of the respiratory movement 

 the character of the cough, and the information derived fro 

 auscultation and percussion. 



Shape of the Cavity of the Chest. In healthy animals tl 

 two sides of the chest should be symmetrical. A depression c 

 one side means pain in that portion of the chest, dry pleuriti 

 recent fractures of the ribs, one-sided contraction of the lung afti 

 a rapid absorption of the exudate of pleurisy. In a case whe: 

 there is a fractured rib there may be a protrusion in one plac 

 an inflammatory condition of the ribs, and tumors of the wa 

 of the chest; when the whole chest seems swollen it indicati 

 double pleuritis, with a great amount of exudate present; wht 

 only the posterior half of the thorax seems distended and we fir 

 the abdomen enlarged, it indicates ascites, tumors, or collections i 

 the abdominal cavity. 



Sensitiveness to Pressure. This is produced by a number < 

 inflammatory conditions of the skin and subcutis, the ribs, or tl 

 intercostal muscles in cases of muscular rheumatism, in fractui 

 of the ribs, and quite frequently in pleuritis. 



Number and Character of the Eespiratory Movement! 

 Normal breathing is performed in the dog, as in other animal 

 through muscular action in inspiring, and the elasticity of the tissu 

 of the lungs and the walls of the chest in expiration; this is als 

 aided by the pressure of the intestines on the diaphragm. It : 



